This is the launcher re-loading. If you are coming from an app that uses lots of memory, especially thanks to the Sense memory tweaks, this will happen. This is not a bug, just the way it is with a "heavy" launcher. You could try another launcher like Nova, but there is no guarantee it will not happen there as well. The longer you are away from your homescreen and the more memory intensive the app(s) you have running, the more likely this will happen. Very common after dumping from a game, or something equally as intensive. Less common if you are not using the Sense launcher. At the least, delete any screens you do not use to lessen the impact.
Chrome has been the suck for a long time now on not just this device for me, but on my tablet and across Sense/AOSP. I have gone back to the normal browser and only enable Chrome to test new releases in the hopes it is better.